scholarly journals V-Shaped Formation Control for Robotic Swarms Constrained by Field of View

2018 ◽  
Vol 8 (11) ◽  
pp. 2120 ◽  
Author(s):  
Jian Yang ◽  
Xin Wang ◽  
Peter Bauer

By forming a specific formation during motion, the robotic swarm is a good candidate for unknown region exploration applications. The members of this kind of system are generally low complexity, which limits the communication and perception capacities of the agents. How to merge to the desired formation under those constraints is essential for performing relevant tasks. In this paper, a limited visual field constrained formation control strategy inspired by flying geese coordinated motion is introduced. Usually, they flock together in a V-shape formations, which is a well-studied phenomenon in biology and bionics. This paper illustrates the proposed methods by taking the research results from the above subjects and mapping them from the swarm engineering point of view. The formation control is achieved by applying a behavior-based formation forming method with the finite state machine while considering anti-collision and obstacle avoidance. Furthermore, a cascade leader–follower structure is adopted to achieve the large-scale formations. The simulation results from several scenarios indicate the presented method is robust with high scalability and flexibility.

Author(s):  
B. Aparna ◽  
S. Madhavi ◽  
G. Mounika ◽  
P. Avinash ◽  
S. Chakravarthi

We propose a new design for large-scale multimedia content protection systems. Our design leverages cloud infrastructures to provide cost efficiency, rapid deployment, scalability, and elasticity to accommodate varying workloads. The proposed system can be used to protect different multimedia content types, including videos, images, audio clips, songs, and music clips. The system can be deployed on private and/or public clouds. Our system has two novel components: (i) method to create signatures of videos, and (ii) distributed matching engine for multimedia objects. The signature method creates robust and representative signatures of videos that capture the depth signals in these videos and it is computationally efficient to compute and compare as well as it requires small storage. The distributed matching engine achieves high scalability and it is designed to support different multimedia objects. We implemented the proposed system and deployed it on two clouds: Amazon cloud and our private cloud. Our experiments with more than 11,000 videos and 1 million images show the high accuracy and scalability of the proposed system. In addition, we compared our system to the protection system used by YouTube and our results show that the YouTube protection system fails to detect most copies of videos, while our system detects more than 98% of them.


2017 ◽  
Vol 4 (1) ◽  
pp. 41-61
Author(s):  
Pelin Sönmez ◽  
Abulfaz Süleymanov

Türkiye, Cumhuriyet tarihinin en yoğun zorunlu göç dalgasını 2011 yılından bu yana süren Suriye Savaşı ile yaşamaktadır. Suriye vatandaşlarının geçici koruma statüsü altında Türkiye toplumuna her açıdan entegrasyonları günümüzün ve geleceğin politika öncelikleri arasında düşünülmelidir. Öte yandan ülkeye kabul edilen sığınmacıların kendi kültürel kimliğini kaybetmeden içinde yaşadığı ev sahibi topluma uyumu, ortak yaşam kültürünün gelişmesi açısından önem arz etmektedir. Bu makalede, "misafir" olarak kabul edilen Suriyeli vatandaşların Türk toplumunca kabul edilmeleri ve dışlanma risklerinin azaltılmasına yönelik devlet politikaları ortaya konularak, üye ve aday ülkelere göçmenlerin dışlanmasını önlemek için Avrupa Birliği (AB) tarafından sunulan hukuki yapı ve kamu hizmeti inisiyatifleri incelenmekte, birlikte yaşam kültürü çerçevesinde Suriyeli vatandaşlara yönelik  toplumsal kabul düzeyleri ele alınmaktadır. Çalışma iki ana bölümden oluşmaktadır: göçmen ve sığınmacılara karşı toplumsal dışlanmayı engellemek için benimsenen yasa ve uygulamaların etkisi ve İstanbul-Sultanbeyli bölgesinde Suriyeli sığınmacılarla ilgili toplumsal algı çalışmasının sonuçları. Bölgede ikamet eden Suriyelilere yönelik toplumsal kabul düzeyinin yüksek olduğu görülürken, halkın Suriyelileri kendilerine  kültürel ve dini olarak yakın hissetmesi toplumsal kabul düzeyini olumlu etkilemektedir. ABSTRACT IN ENGLISHAn evaluation of the European Union and Turkish policies regarding the culture of living togetherThis article aims to determine the level of social acceptance towards Syrians within the context of cohabitation culture by evaluating EU’s legal structure and public service initiatives in order to prevent Syrian refugees from being excluded in member and candidate countries and by revealing government policies on acceptance of Syrians as “guest” by Turkish society and minimizing the exclusion risks of them. This article consists of two main parts, one of which is based on the effects of law and practices preventing refugees and asylum seekers from social exclusion, and the other is on the results of social perception on Syrians in Sultanbeyli district of Istanbul. At the end of 5-years taking in Syrian War, it is obvious that most of more than 3 million Syrian with unregistered ones in Turkey are “here to stay”. From this point of view, the primary scope of policies should be specified in order to remove side effects of refugee phenomenon seen as weighty matter by bottoming out the exclusion towards those people. To avoid possible large-scale conflicts or civil wars in the future, the struggle with exclusion phenomenon plays a crucial role regarding Turkey’s sociological situation and developing policies. In the meaning of forming a model for Turkey, a subtitle in this article is about public services for European-wide legal acquis and practices carried out since 1970s in order to prevent any exclusion from the society. On the other hand, other subtitles are about legal infrastructure and practices like Common European Asylum and Immigration Policies presented in 2005, and Law on Foreigners and International Protection introduced in 2013. In the last part of the article, the results of a field survey carried out in a district of Istanbul were used to analyze the exclusion towards refugees in Turkey. A face-to-face survey was randomly conducted with 200 settled refugees in Sultanbeyli district of Istanbul, and their perceptions towards Syrian people under temporary protection were evaluated. According to the results, the level of acceptance for Syrians living in this district seems relatively high. The fact that Turkish people living in the same district feel close to Syrian refugees culturally and religiously affect their perception in a positive way: however, it is strikingly seen and understood that local residents cop an attitude on the refugees’ becoming Turkish citizens.


The success of the Program of housing stock renovation in Moscow depends on the efficiency of resource management. One of the main urban planning documents that determine the nature of the reorganization of residential areas included in the Program of renovation is the territory planning project. The implementation of the planning project is a complex process that has a time point of its beginning and end, and also includes a set of interdependent parallel-sequential activities. From an organizational point of view, it is convenient to use network planning and management methods for project implementation. These methods are based on the construction of network models, including its varieties – a Gantt chart. A special application has been developed to simulate the implementation of planning projects. The article describes the basic principles and elements of modeling. The list of the main implementation parameters of the Program of renovation obtained with the help of the developed software for modeling is presented. The variants of using the results obtained for a comprehensive analysis of the implementation of large-scale urban projects are proposed.


Author(s):  
Angela Dranishnikova

In the article, the author reflects the existing problems of the fight against corruption in the Russian Federation. He focuses on the opacity of the work of state bodies, leading to an increase in bribery and corruption. The topic we have chosen is socially exciting in our days, since its significance is growing on a large scale at all levels of the investigated aspect of our modern life. Democratic institutions are being jeopardized, the difference in the position of social strata of society in society’s access to material goods is growing, and the state of society is suffering from the moral point of view, citizens are losing confidence in the government, and in the top officials of the state.


2020 ◽  
Vol 27 (2) ◽  
pp. 105-110 ◽  
Author(s):  
Niaz Ahmad ◽  
Muhammad Aamer Mehmood ◽  
Sana Malik

: In recent years, microalgae have emerged as an alternative platform for large-scale production of recombinant proteins for different commercial applications. As a production platform, it has several advantages, including rapid growth, easily scale up and ability to grow with or without the external carbon source. Genetic transformation of several species has been established. Of these, Chlamydomonas reinhardtii has become significantly attractive for its potential to express foreign proteins inexpensively. All its three genomes – nuclear, mitochondrial and chloroplastic – have been sequenced. As a result, a wealth of information about its genetic machinery, protein expression mechanism (transcription, translation and post-translational modifications) is available. Over the years, various molecular tools have been developed for the manipulation of all these genomes. Various studies show that the transformation of the chloroplast genome has several advantages over nuclear transformation from the biopharming point of view. According to a recent survey, over 100 recombinant proteins have been expressed in algal chloroplasts. However, the expression levels achieved in the algal chloroplast genome are generally lower compared to the chloroplasts of higher plants. Work is therefore needed to make the algal chloroplast transformation commercially competitive. In this review, we discuss some examples from the algal research, which could play their role in making algal chloroplast commercially successful.


2021 ◽  
Vol 8 (1) ◽  
Author(s):  
Bilal Elghadyry ◽  
Faissal Ouardi ◽  
Sébastien Verel

AbstractWeighted finite-state transducers have been shown to be a general and efficient representation in many applications such as text and speech processing, computational biology, and machine learning. The composition of weighted finite-state transducers constitutes a fundamental and common operation between these applications. The NP-hardness of the composition computation problem presents a challenge that leads us to devise efficient algorithms on a large scale when considering more than two transducers. This paper describes a parallel computation of weighted finite transducers composition in MapReduce framework. To the best of our knowledge, this paper is the first to tackle this task using MapReduce methods. First, we analyze the communication cost of this problem using Afrati et al. model. Then, we propose three MapReduce methods based respectively on input alphabet mapping, state mapping, and hybrid mapping. Finally, intensive experiments on a wide range of weighted finite-state transducers are conducted to compare the proposed methods and show their efficiency for large-scale data.


Author(s):  
Rong Ran ◽  
Hayoung Oh

AbstractSparse-aware (SA) detectors have attracted a lot attention due to its significant performance and low-complexity, in particular for large-scale multiple-input multiple-output (MIMO) systems. Similar to the conventional multiuser detectors, the nonlinear or compressive sensing based SA detectors provide the better performance but are not appropriate for the overdetermined multiuser MIMO systems in sense of power and time consumption. The linear SA detector provides a more elegant tradeoff between performance and complexity compared to the nonlinear ones. However, the major limitation of the linear SA detector is that, as the zero-forcing or minimum mean square error detector, it was derived by relaxing the finite-alphabet constraints, and therefore its performance is still sub-optimal. In this paper, we propose a novel SA detector, named single-dimensional search-based SA (SDSB-SA) detector, for overdetermined uplink MIMO systems. The proposed SDSB-SA detector adheres to the finite-alphabet constraints so that it outperforms the conventional linear SA detector, in particular, in high SNR regime. Meanwhile, the proposed detector follows a single-dimensional search manner, so it has a very low computational complexity which is feasible for light-ware Internet of Thing devices for ultra-reliable low-latency communication. Numerical results show that the the proposed SDSB-SA detector provides a relatively better tradeoff between the performance and complexity compared with several existing detectors.


Morphology ◽  
2021 ◽  
Author(s):  
Rossella Varvara ◽  
Gabriella Lapesa ◽  
Sebastian Padó

AbstractWe present the results of a large-scale corpus-based comparison of two German event nominalization patterns: deverbal nouns in -ung (e.g., die Evaluierung, ‘the evaluation’) and nominal infinitives (e.g., das Evaluieren, ‘the evaluating’). Among the many available event nominalization patterns for German, we selected these two because they are both highly productive and challenging from the semantic point of view. Both patterns are known to keep a tight relation with the event denoted by the base verb, but with different nuances. Our study targets a better understanding of the differences in their semantic import.The key notion of our comparison is that of semantic transparency, and we propose a usage-based characterization of the relationship between derived nominals and their bases. Using methods from distributional semantics, we bring to bear two concrete measures of transparency which highlight different nuances: the first one, cosine, detects nominalizations which are semantically similar to their bases; the second one, distributional inclusion, detects nominalizations which are used in a subset of the contexts of the base verb. We find that only the inclusion measure helps in characterizing the difference between the two types of nominalizations, in relation with the traditionally considered variable of relative frequency (Hay, 2001). Finally, the distributional analysis allows us to frame our comparison in the broader coordinates of the inflection vs. derivation cline.


Data ◽  
2021 ◽  
Vol 6 (1) ◽  
pp. 4
Author(s):  
Evgeny Mikhailov ◽  
Daniela Boneva ◽  
Maria Pashentseva

A wide range of astrophysical objects, such as the Sun, galaxies, stars, planets, accretion discs etc., have large-scale magnetic fields. Their generation is often based on the dynamo mechanism, which is connected with joint action of the alpha-effect and differential rotation. They compete with the turbulent diffusion. If the dynamo is intensive enough, the magnetic field grows, else it decays. The magnetic field evolution is described by Steenbeck—Krause—Raedler equations, which are quite difficult to be solved. So, for different objects, specific two-dimensional models are used. As for thin discs (this shape corresponds to galaxies and accretion discs), usually, no-z approximation is used. Some of the partial derivatives are changed by the algebraic expressions, and the solenoidality condition is taken into account as well. The field generation is restricted by the equipartition value and saturates if the field becomes comparable with it. From the point of view of mathematical physics, they can be characterized as stable points of the equations. The field can come to these values monotonously or have oscillations. It depends on the type of the stability of these points, whether it is a node or focus. Here, we study the stability of such points and give examples for astrophysical applications.


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